Gowalla

What is Gowalla?
Gowalla is a location-based social network that uses game mechanics as a motivator to go places, do things and meet friends.

Players use a GPS-enable smartphone to check in at places of interest, share their location with friends, and leave comments about their travels. They are credited for their efforts with a game-like achievement system that rewards visiting both common and unique locations with a variety of iconic stamps.
Source: TechCrunch

Go Mobile
iPhone
Android
Blackberry
Palm (TBA)

Video Introduction

Company Details:
Location: Austin, Texas
Founded: 2009
Funding: $8.4M
Source: TechCrunch